This Multi-Project SPIRAT Program aims to develop a peptide based immunotherapeutic vaccine for HIV-1 infection. The central strategy is to control and/or eradicate chronic retroviral infection through the induction of virus specific, MHC class 1 -restricted cytolytic T lymphocytes (CTL) targeted at highly con served regions of HIV-1 proteins. The primary goal of the Program is to test the validity of this experimental hypothesis directly in man. To accomplish this goal, the Program unites leading experts in the development of peptide based immunotherapeutic for viral infection at Cytel Corporation with established AIDS investigators at Massachusetts General Hospital who have a long-term scientific interest in evaluating the role of CTL in AIDS at the laboratory and clinical level. The SPIRAT mechanism provides an unique opportunity to establish this Multi-Project Program capable of developing a novel AIDS therapeutic vaccine in a step-wise, scientifically rational fashion leading to the timely introduction of a vaccine candidate into clinical testing.